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| author | James Forshaw <forshaw@google.com> | 2014-08-23 14:39:48 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-09-05 16:28:37 -0700 |
| commit | d0e6e29e2c9820d39b83fa275bf68c7c8bc7935e (patch) | |
| tree | 0109f60fe6bafcce15927d40f24622b833af1601 | |
| parent | 17912b6285ac739e9c461a3601a4a7c7eda7a5a8 (diff) | |
| download | lwn-d0e6e29e2c9820d39b83fa275bf68c7c8bc7935e.tar.gz lwn-d0e6e29e2c9820d39b83fa275bf68c7c8bc7935e.zip | |
USB: whiteheat: Added bounds checking for bulk command response
commit 6817ae225cd650fb1c3295d769298c38b1eba818 upstream.
This patch fixes a potential security issue in the whiteheat USB driver
which might allow a local attacker to cause kernel memory corrpution. This
is due to an unchecked memcpy into a fixed size buffer (of 64 bytes). On
EHCI and XHCI busses it's possible to craft responses greater than 64
bytes leading a buffer overflow.
Signed-off-by: James Forshaw <forshaw@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/serial/whiteheat.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/usb/serial/whiteheat.c b/drivers/usb/serial/whiteheat.c index 347caad47a12..5e3dd9f87ff5 100644 --- a/drivers/usb/serial/whiteheat.c +++ b/drivers/usb/serial/whiteheat.c @@ -521,6 +521,10 @@ static void command_port_read_callback(struct urb *urb) dev_dbg(&urb->dev->dev, "%s - command_info is NULL, exiting.\n", __func__); return; } + if (!urb->actual_length) { + dev_dbg(&urb->dev->dev, "%s - empty response, exiting.\n", __func__); + return; + } if (status) { dev_dbg(&urb->dev->dev, "%s - nonzero urb status: %d\n", __func__, status); if (status != -ENOENT) @@ -541,7 +545,8 @@ static void command_port_read_callback(struct urb *urb) /* These are unsolicited reports from the firmware, hence no waiting command to wakeup */ dev_dbg(&urb->dev->dev, "%s - event received\n", __func__); - } else if (data[0] == WHITEHEAT_GET_DTR_RTS) { + } else if ((data[0] == WHITEHEAT_GET_DTR_RTS) && + (urb->actual_length - 1 <= sizeof(command_info->result_buffer))) { memcpy(command_info->result_buffer, &data[1], urb->actual_length - 1); command_info->command_finished = WHITEHEAT_CMD_COMPLETE; |